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The Development of SONAR As a Tool in Marine Biological Research in the Twentieth Century

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The Development of SONAR As a Tool in Marine Biological Research in the Twentieth Century Hindawi Publishing Corporation International Journal of Oceanography Volume 2013, Article ID 678621, 9 pages http://dx.doi.org/10.1155/2013/678621 Review Article The Development of SONAR as a Tool in Marine Biological Research in the Twentieth Century John A. Fornshell1 and Alessandra Tesei2 1 National Museum of Natural History, Department of Invertebrate Zoology, Smithsonian Institution, Washington, DC, USA 2 AGUAtech, Via delle Pianazze 74, 19136 La Spezia, Italy Correspondence should be addressed to John A. Fornshell; [email protected] Received 3 June 2013; Revised 16 September 2013; Accepted 25 September 2013 Academic Editor: Emilio Fernandez´ Copyright © 2013 J. A. Fornshell and A. Tesei. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The development of acoustic methods for measuring depths and ranges in the ocean environment began in the second decade of the twentieth century. The two world wars and the “Cold War” produced three eras of rapid technological development in the field of acoustic oceanography. By the mid-1920s, researchers had identified echoes from fish, Gadus morhua, in the traces from their echo sounders. The first tank experiments establishing the basics for detection of fish were performed in 1928. Through the 1930s, the use of SONAR as a means of locating schools of fish was developed. The end of World War II was quickly followed by the advent of using SONAR to track and hunt whales in the Southern Ocean and the marketing of commercial fish finding SONARs for use by commercial fisherman. The “deep scattering layer” composed of invertebrates and fish was discovered in the late 1940s onthe echo sounder records. SONARs employing high frequencies, broadband, split beam, and multiple frequencies were developed as methods for the detection, quantification and identification of fish and invertebrates. The study of fish behavior has seen someuse of passive acoustic techniques. Advancements in computer technology have been important throughout the last four decades of the twentieth century. 1. Introduction research. Following the war, active acoustic ranging devices in the form of echo sounders began to be employed in During the twentieth century, the use of acoustics to study measuring ocean depths. Soon, acousticians began to rec- life in the oceans was developed into a significant tool for ognize the ability to detect marine organisms, principally research in marine biology. The purpose of this paper is to fish, using these devices. The use of sound to detect fishas briefly recount the process by which the use of acoustics as a a tool in the fishing industry and fisheries research began biological research tool took place. The general pattern was a slow development from the mid-1920s until the out-break the development of acoustic technology for nonbiological of the Second World War. This conflict produced an even research uses, navigation and military operations to name larger stimulus for the development of knowledge about the two and then the application of that technology to the behavior of sound in the marine environment. Following detection and study of marine life. By the end of the twentieth the Second World War, the development of SONAR as a century, acoustic technology had become a significant factor tool in biological research accelerated constantly. The “Cold in marine biological research. Marine biologists were devel- War” also led to the development of advanced knowledge of oping acoustic equipment for the specific purpose of studying ocean acoustics and sophisticated passive SONAR technology life in the oceans. which became available following the collapse of the Soviet The development of modern acoustic technologies for use Union in 1991. In this brief history, the developments are in the ocean environment began during the second decade chronicled in terms of the first uses of acoustics for biological of the twentieth century. The First World War provided a work prior to World War II; subsequent to this conflict, for significant stimulus for the advancement of ocean acoustics theperiodfrom1946to2000,marinemammalresearch, 2 International Journal of Oceanography plankton biology research, and fisheries biology are each soundpropagationinthesea.Theacronym,SONAR(SOund treated as a separate thread in the development of SONAR Navigation And Ranging), was proposed by F. V. (Ted) as a tool in biological research. HuntofHarvardUniversityin1942andisthetermmost commonly applied to acoustic detection devices, both active 2. Early Developments and passive [1, 15]. This new found knowledge was quickly applied to more peaceful enterprises, the commercial whaling Many historians site the sinking of the RMS Titanic as and fishing industries in particular. the immediate stimulus for the development of underwa- ter acoustic ranging technology. In response to this event, 3. SONAR Applications in the Study of Reginald Fessenden developed the “Fessenden oscillator” to Marine Mammals detect icebergs and the sea floor. This device was first used on the US Coast Guard Cutter Miami in 1914 [1, 2]. The Following the end of World War II, 1946, surplus military threat of German submarines during the First World War led SONAR units were fitted onto some whale catcher vessels to significant advances in underwater acoustic technology. of European nations and were used to hunt whales in the The most important contributions in the development of Southern Ocean. The use of this equipment greatly improved active acoustic detection devices were made by the team the efficiency of the whaler’s efforts in killing whales. The first of the French physicist, Paul Langevin, and the Russian commercial acoustic detection equipment for the hunting Constantin Chilowsky. These workers produced an acoustic of whales was being manufactured and marketed by the transmitter which could be mounted on a ship. Their initial Kelvin-Hughes Company in 1948. The use of SONAR to instrument emitted sounds at a frequency of 38 kHz (see actively track a whale with the technology available in the [1] for a complete summary of the principles of underwater late 1940s was limited to ranges of about 1 mile, 1600 m, with acoustics). By the year 1919, a device working in the frequency an optimal range from 450 m to 900 m. By 1956, more than range from 20 kHz to 50 kHz was being installed on warships. forty catcher boats from Norway, Great Britain, and Denmark R. W. Boyle coined the acronym ASDIC (Anti-Submarine were equipped with the Kelvin-Hughes Echowhale Finder. Detection Investigation Committee) for use in reference The installation of SONAR equipment on pelagic Japanese to underwater acoustic detection devices [1–3]. In 1922, whale catcher vessels began in 1958 and was universal by 1962. Harvey Hayes working on the USS Stewart, a navy destroyer, The installation of acoustic detection equipment in Japanese introduced the use of the echo sounder to measure water coastal whale catcher vessels began earlier, in 1950, but was depths; he ran a transect across the Atlantic Ocean from never in use on all members of the coastal whaling fleet16 [ ]. Newport, Rhode Island to Gibraltar, making a total of 900 In the case of baleen whales, the SONAR pings frightened depth measurements. Between 1923 and 1928, US Coast and the whales resulting in an escape behavior in which the Geodetic Survey vessels were fitted with deepwater sounding animals swam at high speed near the surface in a straight instruments. Similar equipment was being fitted on survey line away from the sound source. This caused them to tire shipsoftheRoyalNavyHydrographicOfficeandtheGerman more quickly and made it easier to follow the whale and Navy’s research ship Meteor. This marks the beginning of the kill it. In hunting sperm whales, which tend to dive to great use of acoustics in an organized fashion to study the marine depths when being pursued, the SONAR was used to track environment [4]. the animal during its dive and to position the catcher vessels Portier reported on the possibility of detecting sardines neartheplacewherethewhalesurfaces.Spermwhaleshave using an echo sounder [5]. In 1927, Rallier du Baty was been observed to modify their click frequency to match that thefirsttoattributefalseechoesonechogramrecordings of a tracking SONAR [16]. from the Grand Banks in the western North Atlantic as In 1963, Walker, using passive listening equipment, being indications of the presence of cod, Gadus morhua [6]. reported on the detection of underwater sounds with Two years later, in 1929, Kimura published the results of widespread geographic distribution, apparently of biological experiments in which he demonstrated that fish could be origin. The low-frequency, 20 Hz, sounds were detected in the detected with the relatively simple acoustic equipment of his North Atlantic and North Pacific Oceans. The trains of pulses time [7]. In 1935, Edgell using an echo sounder on the Royal with a period of approximately ten seconds were observed to Navy Hydrographic Office survey vessel HMS Challenger was (a) be point sources, (b) to move with a speed of five knots able to detect fish in the North Atlantic8 [ ]. In the mid-1930s, orless,and(c)tobesomewhatintermittent,thatis,tobe the use of echo sounders by fishing vessels began on a very punctuated by periods of silence. The conclusion that Walker limited scale [9]. Norwegian fisheries biologists used echo reached was that they approximated the sounds of a large sounders to survey cod populations in Vestfjord and, by 1937, mammal’s heartbeat. They would have been less audible while included acoustic surveys of herring [10–12]. Balls, who was the whale was on the surface and large marine mammals have captain of the herring drifter Violet and Rose, used the echo depressed heart rates when diving [17]. sounder on his vessel to improve the efficiency of his fishing During the “Cold War,” 1948 to 1990, the reliance on pas- effort [13, 14].
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